North Tahoe sixth-graders study how erosion affects their backyard
TAHOE CITY, Calif. — As part of the end of school for Mrs. Fagnani’s sixth-grade science class, students at North Tahoe Middle School created their own research projects on erosion around their school and in the Lake Tahoe Basin.
Building off of previous earth science lessons, students put their knowledge into practice asking and experimentally answering questions including: “How do different types plants prevent erosion?” “How does the type and steepness of soil affect erosion?” and “How much sediment-runoff does 1 liter of water cause?”
Students collected data around their school during class time before analyzing and presenting their findings back to their classmates.
Student Research Highlights
Alessandra, Jasmin, Sebastian, and Alfredo studied the root structures in different types of grasses. In addition to getting an up close understanding of roots hold soil in place, they found that most local grasses have roots that are half as deep as the plant is tall.
Although the roots weren’t as deep as the group expected, the roots were incredibly dense, which is why they are great at preventing runoff.
Jake, Eduardo, Ava, Vero, and Anthony surveyed the area around their school to learn how the amount of vegetation coverage and steepness of a slope affects erosion.
They found that on average slopes without vegetation had nearly double the amount of erosion than slopes with vegetation. The group also found a small correlation between the steepness of a slope and increased erosion.
Bryan, Kacey, Jude, Pamela, Katelyn, and Brayden’s experiment worked to measure how much erosion water would cause on different slopes.
They set up 20 different test slopes of different steepness and on varying soil types. They then poured known amounts of water down the slope until a cubic inch of soil was displaced.
The group found that grass clearly held back sediment the best Fine grain soil eroded the fastest as very little of the water was absorbed into the soil.
This program was run by instructors from Headwaters Science Institute, a local nonprofit, and was funded by the Truckee Tahoe Airport Foundation, the Truckee Rotary, and contributions from individual donors.
This article was provided by Headwaters Science Institute. Visit headwatersscienceinstitute.org to learn more.